Remove root key

We don't use root key to verify NVIDIA driver
signature anymore.

BUG=b/391455624
TEST=prsubmit
RELEASE_NOTE=None

cos-patch: bug
Change-Id: I7bdd183051abb14b62f5b30d8372edf7c661d94e
Signed-off-by: He Gao <hegao@google.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/93061
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Shuo Yang <gshuoy@google.com>
Main-Branch-Verified: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
3 files changed